title: The novel assay method for nicotine metabolism to cotinine using high performance liquid chromatography.
abstract: Nicotine is the primary psychoactive component in tobacco. It is taken into the body by tobacco smoking, and mainly metabolized to cotinine in the hepatic cytochrme P450 (CYP) 2A6. The objective of this study was to develop a sensitive method for the determination of nicotine metabolism to cotinine using HPLC. The internal standard, trans-4'-carboxycotinine methyl ester was synthesized with a simple method. The nicotine and cotinine were separated completely and detected by C(18) 5-µm analytical column (L-column Octa decyl silyl (ODS), 150 mm × 4.6 mm i.d.) equipped with a C(18) 5-µm guard column (L-column ODS, 10 mm × 4.6 mm i.d.) and ultraviolet detection at 260 nm. The detection limit of the assay was 0.05 µM for cotinine (n=5, R.S.D) and 0.1 µM for nicotine. Thus the present results provided a sensitive and useful method for the determination of nicotine metabolism catalyzed by CYP2A6.
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Engineering, Kinki University, Higashiosaka, Osaka, Japan. miyazawa@apch.kindai.ac.jp
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Miyazawa
authors.forename: Yumi
authors.initials: Y
authors.lastname: Kawauchi
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Okuno
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Oda
mesh_terms: D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D003367:Cotinine / Q000032:analysis*; D065637:Cytochrome P-450 CYP2A6; D006801:Humans; D009538:Nicotine / Q000032:analysis* / Q000378:metabolism; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D013056:Spectrophotometry, Ultraviolet
chemical_list: D011994:Recombinant Proteins; D009538:Nicotine; D001189:Aryl Hydrocarbon Hydroxylases; C585710:CYP2A6 protein, human; D065637:Cytochrome P-450 CYP2A6; D003367:Cotinine